Coordinated control of heat-power integrated energy system using zone model predictive control with variable zone width

Abstract

• Evaluation of the thermal-electric interactions within the IES. • Heat-power coordinated control scheme is proposed to improve the flexibility of IES. • Zone-MPC is developed for the heat control to unlock better power side performance. • Zone width variation function is designed to release optimization space flexibly. • The applicability of the proposed method is fully demonstrated in various scenarios. Integrated energy system (IES) with high-penetration of renewable energy is one of the important development directions of future energy systems. However, the fluctuations on both the source and load sides bring great challenges to the stable operating of IES, and the strong interactions between multiple types of energies further increase the control difficulties. This paper investigates the dynamic differences in the thermal and power processes of the IES by simulating a typical combined heat and power IES model. The response speed at the thermal side is found to be over five times slower than that at the power side. Further considering the different control requirements for the heat and power supply, a novel heat-power coordinated control strategy based on the idea of zone model predictive control is proposed to improve the flexibility of the IES. The conventional set-point tracking control is applied at the power side to eliminate the offset between the supply and demand quickly, while the thermal side control is relaxed to a variable-width zone control to unlock superior regulation performance at the power side. A series of simulation studies are carried out under normal, frequent electric-side disturbance, extreme weather and low-carbon operating scenarios. The results demonstrate that the proposed approach can greatly improve the electrical control performance of the IES with slight degradations on the thermal side. This paper points to a new way of using zone predictive control to exploit the differences between multiple forms of energies for the flexible operation of modern energy systems.